* Yarrow (Achillea ‘Moonshine’) – Zone 3 This is listed as 1 of 10 Best Perennials of All Time by Heritage Perennials who claim that Yarrow (Achillea ‘Moonshine’) has been around for awhile and it is considered one of the best perennials of all time. A classic, it offers great looks, outstanding performance and combines well with its neighbours making it a natural for this list. Huge canary-yellow clusters last all summer long while the feathery, silver-grey foliage remains attractive all season. Exceptional drought tolerance once established.” It is planted in my Country Lane in the City Garden and in my September Surprise Garden.